A newly discovered mural is one of many in 12 of Afghanistan’s famed Bamian caves that show evidence of an oil-based binder. The binder was used to dry paint and help it adhere to rocky surfaces.The murals—and the remains of two giant, destroyed Buddhas—include the world’s oldest known oil-based paint, predating European uses of the substance by at least a hundred years, scientists announced late last month.Researchers made the discovery while conducting a chemical analysis as part of preservation and restoration efforts at Bamian, which lies about 145 miles (240 kilometers) northwest of the Afghan capital, Kabul.Seen in a 2005 photo, a towering alcove in Afghanistan’s Bamian Valley cliffs shows the former home of a giant Buddha statue. Dating to between the fifth and ninth centuries A.D., the statue was one of a pair destroyed by Taliban officials in 2001.Researchers have found that the paint used on the Buddhas, along with murals in 12 of 50 painted Bamian caves, contained oil-based binders—the world’s oldest known examples of oil paintings.A Buddhist mural dated to around the seventh century A.D. is one of many in Afghanistan’s Bamian Valley that were recently found to contain oil- and resin-based paints.The use of the substances at such an early date is a surprise, since they require sophisticated knowledge of chemical properties, scientists say.Oil is used in paints to help fix dyes and help them adhere to surfaces. It also changes a paint’s drying time and viscosity.Europeans began using oil in their pictures by about 800 A.D., but the new research on the Central Asian pushes back the onset of oil-based painting by at least a hundred years.Researchers hope to find even earlier examples by studying other Central Asian sites.Another mural from the Bamian cave Foladi 6 has been dated to the eighth century A.D. Its artists used an oil-based paint, scientists say, in an early example of mixing organic binding agents with pigments